Will New Blu-ray Drives Suck Your Laptop Battery Dry?

Now that Sony’s Blu-ray technology has won the high-def format war, computer manufacturers must tackle its power-hungry playback performance.
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Watching a Blu-ray movie in all its high-definition glory on your laptop may finally become an affordable prospect this year. Just don't wander too far from a power outlet.

With the Sony-backed HD format emerging victorious from a two-year showdown with Toshiba's HD DVD, many laptop manufacturers are now scrambling to add Blu-ray drives in their desktop and notebook lineups. Next month, Dell will even introduce a sub-$1,000 Blu-ray notebook, according to Brian Zucker, a technology strategist for the company.

But the promise of viewing an increasing variety of HD movies on your laptop may be overshadowed by ongoing concerns over the technology's vampiric effect on battery life. Indeed, if the first generation of Blu-ray equipped laptops are any indication, you might not get more than halfway through that movie before running out of juice completely, analysts say.

"If you bought an iPhone and you couldn't watch a two-hour movie, which you barely can now, that would be a huge problem," Martin continued.

Granted, batteries suck (along with other annoyances like spam filters and plastic packaging). That's largely because there is no Moore's Law for batteries. If battery power capacity improves 1 percent a year, that's considered pretty good. Batteries are more often afterthoughts for an industry obsessed with cramming as many new features into a notebook as possible.

Introducing Blu-ray drives to the mobile mix certainly isn't going to help matters. For now, the laptop manufacturers that have offered Blu-ray drives have also avoided revealing the precise effects of Blu-ray playback on battery life. That's probably for a very good reason, as some claim battery life can top out at one hour in some cases.

"The laser that runs the show [in Blu-ray players] is a very high-power laser," notes Mercury Research analyst Dean McCarron. That laser is one of the main things that conspire to raise power consumption.

The other part of the equation has to do with the process of decoding data from a Blu-ray disc and turning it into moving images on your screen. When Blu-ray was first introduced, this process was all done in software, which is very taxing on the CPU, eating up processing cycles and power.

"Any time you introduce a new technology like this, the initial products tend to be more power-hungry," McCarron says. "Once you get to a certain point, though, the industry usually starts the refinement process."

That process is actually well underway, according to the Blu-ray Disc Association. "In the first generation of laptops that had Blu-ray drives, [power drain] was an issue," a Blu-ray spokesperson said, "but that's been resolved."

The solution has come by offloading some of the decode process onto other system hardware, namely the graphics processing unit, according Dell's Zucker, who also sits on a committee of the Blu-ray Association.

"We looked at playing DVDs and Blu-ray discs, and our early data showed that it could knock [battery life] down to half when playing a Blu-ray disc," Zucker says. He also points out that the main reason we've only seen Blu-ray drives in high-end laptops to date is because you also need a high-end processor to do that decoding.

"All that's changed now, because we have decode assistance from the graphics core," Zucker says, thanks to sophisticated new graphics cards from Nvidia and ATI.

There are some Blu-ray laptops that have sufficient battery capacity for playback of two movies back-to-back on one charge, Zucker says, declining to give specifics. Two models might be Dell's XPS M1530 and Inspiron 1420, which the company claims will support 4½ hours of Blu-ray playback.

Many analysts contacted by Wired.com note that even though laptop makers will be eager to add Blu-ray drives into their lineups, the desktop will likely remain the logical home for Blu-ray in the near term. On the desktop, most consumers won't have to worry about power issues and will also have larger monitors to enjoy all that high-definition content.

Ultimately, McCarron expects a scenario similar to what happened with the first DVD drives. Substantial power drain will be an issue at first, but the technology will be refined in the desktop and then ported to the notebook, eventually eliminating power-consumption problems.